Here is the full list of all 27 Sky Force Anniversary achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Find all the cards.
Collect 200 000 stars.
Rescue your friends 20 times.
Collect all the stars from Stage 3.
Earn 100 medals.
Collect 100 000 stars.
Rescue 1 000 people.
Save 20 000 stars in your bank.
Rescue 5 VIPs.
Destroy at least 15 enemies with one Mega-Bomb.
Destroy 10 000 enemies.
Complete Stage 8 without using power-ups.
Earn 50 medals.
Finish a stage with your health lower than 5%.
Burn through 10 enemies with your Laser.
Destroy all enemy towers on Stage 5.
Save 5 power-ups at the end of the stage.
Rescue 500 people.
Use 3 different power-ups in a single game.
Destroy the lighthouse without touching it.
Destroy 2 500 enemies.
Earn 10 medals.
Ram through an enemy wave with your Energy Shield.
Use any 5 power-ups in a single game.
Rescue 100 people.
Enter the tournament.
Destroy 1 000 enemies.